Euler双流体模型修改曳力模型后发散
-
fluent默认模型收敛，修改后直接发散。提示：
Updating solution at time level N... done. iter continuity u-water u-air v-water v-air vf-air time/iter # Divergence detected in AMG solver: mp-x-momentum -> Decreasing coarsening group size! # Divergence detected in AMG solver: mp-x-momentum -> Increasing relaxation sweeps! # You may try the enhanced divergence recovery with (rpsetvar 'amg/protective-enhanced? #t) # Divergence detected in AMG solver: pressure correction -> Turning off correction scaling! # Divergence detected in AMG solver: pressure correction -> Increasing relaxation sweeps! # You may try the enhanced divergence recovery with (rpsetvar 'amg/protective-enhanced? #t) Error: Divergence detected in AMG solver: pressure correction Error: Divergence detected in AMG solver: pressure correction Error Object: #f这种情况是因为曳力突然为0了，或者无穷大？？？？？那位老司机教教我
-
@东岳 计算了新的曳力系数
#include "udf.h" DEFINE_EXCHANGE_PROPERTY(F_gl, c, mixture_thread, second_col, first_col) { /* coefficient and parameters */ real E_1 = 180; real E_2 = 1.8; real r_p = 0.0015; real d_p = 2 * r_p; /* declaration */ Thread *thread_g, *thread_l; real x_vel_g, y_vel_g; real x_vel_l, y_vel_l; real slip_x, slip_y, abs_slip_vel; real rho_g, rho_l, mu_g, mu_l; real void_g, void_l, void_s; real K_gl, tmp_1, tmp_2; /* find the threads for the gas and liquid */ thread_g = THREAD_SUB_THREAD(mixture_thread, second_col); /* gas */ thread_l = THREAD_SUB_THREAD(mixture_thread, first_col); /* liquid */ /* get phase velocity and fraction */ x_vel_g = C_U(c, thread_g); y_vel_g = C_V(c, thread_g); x_vel_l = C_U(c, thread_l); y_vel_l = C_V(c, thread_l); slip_x = x_vel_g - x_vel_l; slip_y = y_vel_g - y_vel_l; mu_g = C_MU_L(c, thread_g); mu_l = C_MU_L(c, thread_l); rho_g = C_R(c, thread_g); rho_l = C_R(c, thread_l); void_g = C_VOF(c, thread_g); void_l = C_VOF(c, thread_l); void_s = 0.365; /* slip velocity */ abs_slip_vel = sqrt(slip_x * slip_x + slip_y * slip_y); /* compute drag and return drag coeff */ K_gl = (void_g / (void_g + void_l)) * (tmp_1 + tmp_2); tmp_1 = (E_1 * mu_g * pow(1 - void_g, 2) / pow(void_g, 2) / pow(d_p, 2)) * pow((void_s / (1 - void_g)), 3 / 2); tmp_2 = (E_2 * rho_g * abs_slip_vel * (1 - void_g) / void_g / d_p) * pow((void_s / (1 - void_g)), 1 / 3); return K_gl; } -
